The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2000-238455 filed on Aug. 7, 2001 the entire contents thereof is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to an air cleaner, and particularly to a support structure for an element of the air cleaner.
2. Description of Background Art
Elements for air cleaners hitherto known are generally classified as either cylindrical or flat plate shaped. In the case of supporting a cylindrical element in the interior of an air cleaner, there has been known a structure in which a cylindrical element holder is provided on the side of an air cleaner case, the element holder is provided at its peripheral wall portion with a multiplicity of elongated holes in the shape of slits, and the element is fitted to the outside of the element holder (Japanese Utility Model Publication No. 59-10380 (1984)).
On the other hand, an example of using a flat plate shaped element is shown in FIG. 9. FIG. 10 is a sectional view taken along line 10xe2x80x9410 of FIG. 9. A filter paper 3 is placed in a rectangular element chamber 2 formed at a central portion of an element holder 1, whereby the interior of the air cleaner is partitioned into a dirty side 4 and a clean side 5. The clean side of the element 3 is supported by a rectangular element retainer 6. The element retainer 6 is formed by stacking a punching metal 7 and a wire netting 8, and is fitted to the element holder 1 by small screws 9.
The structure in which elongated holes are provided between the element and the clean side, such as the above-mentioned cylindrical element holder, there is a problem in that the opening area is smaller, so that resistance to air passage is higher, which might hamper an increase in the output of the engine. In addition, the elongated holes barely shut off the noise coming from the engine side, so that intake noise is comparatively large.
On the other hand, in the case of a flat plate shaped element shown in FIGS. 9 and 10, although the element retainer 6 can retain the element 3 formed of a filter paper while securing a certain degree of gas passing property, the punching metal 7 is produced by partially punching a plate-like member to simply form a multiplicity of opening portions and, therefore, there is naturally a limitation as to the magnitude of the opening area, and the rate of opening area is at most about 60%. Therefore, it is difficult to enlarge the amount of air taken into the clean side 5, and there is limitation as to the shut-off of noise, so that the same problems as in the case of the cylindrical element holder are left to be solved.
In order to solve the above-mentioned problems, the air cleaner according to the present invention is an air cleaner comprising an element by which the interior of the air cleaner is partitioned into a dirty side and a clean side, and a gas-passing element retainer provided on the side of the clean side of an element holder for supporting the element, wherein the element retainer is in the shape of a louver comprising a plurality of opening portions and a plurality of rectifier portions projected slantly to the upper side of each of the opening portions.
Since the element retainer for supporting the side of the element facing to the clean side is in the shape of a louver, the opening area can securely be sufficiently large and resistance to air passage can be reduced, as compared to the conventional punching metal. In addition, the resistance to air passage can further be reduced also by a rectifying effect of the rectifier portions of the louver. Moreover, when the rectifier portions are formed to be smooth continuous curved surfaces, the rectifying effect can further be increased. Therefore, resistance to passage of cleaned air taken from the element to the clean side can be reduced, so that the amount of air taken in can be increased, which can contribute to enhancement of the output of the engine.
Furthermore, since the rectifier portions of the louver project at a slant to the upper side of the opening portions, the passages of air passing through the opening portions and communicating between the engine side and the element side are bent at the rectifier portions, so that the noise coming from the engine side can be effectively shut off. Therefore, the amount of noise transmitted through the element to the dirty room side can be reduced, resulting in that intake noise can be effectively reduced.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.